Gene Expression Analysis of Lamprey Embryos

Lampreys represent one of two extant jawless vertebrates (cyclostomes) that diverged from jawed vertebrates over 500 million years ago. They are aquatic inhabitants with elongated, eel-shaped bodies and lack paired fins. Instead of jaws, lampreys possess a disc-shaped oral funnel armored with horny teeth. Their larvae, called ammocoetes, exhibit worm-like morphology without the orbits or the oral funnel. From their unique phylogenetic position with curious morphological and developmental traits, lampreys have been widely regarded as a valuable cyclostome model, especially for the study of early vertebrate evolution. However, the accessibility of lamprey embryos is limited because of the difficulty of artificial breeding in the laboratory, which is also seasonally limited. Moreover, their GC-rich DNA sequences have prevented cloning of some genes, as well as genome projects. In this chapter, we illustrate the handling method for the Japanese lamprey, Lethenteron japonicum, and describe the currently available techniques of whole-mount and section in situ hybridizations. We further provide examples of double staining of in situ hybridization combined with neuronal labeling and immunohistochemistry. These techniques allow us to illuminate not only the lamprey developmental mechanisms but also the early evolution of the vertebrates.

Source: Springer protocols feed by Neuroscience - February 20, 2015 Category: Neuroscience Source Type: news